1. Field of the Invention
This invention relates to a disk reproducing apparatus for reproducing recorded information on optical disks placed on a plurality of disk placing portions, and more particularly to a disk identifying device for stopping the disk placing portions at prescribed positions by identifying numbers assigned to the disk placing portions.
2. Description of the Related Art
A disk identifying device which is included in a disk reproducing apparatus for selectively reproducing a plurality of disks identifies a disk number previously assigned using a selective signal for the disk number during a disk reproducing mode, and stops a rotary tray at a reproducing position. Such a disk identifying device requires a rotary tray sensor for detecting the rotary position (position of a disk placing portion) and a disk detecting sensor for detecting whether or not a pertinent disk is located at the disk placing portion.
A disk reproducing apparatus disclosed in JP-A-6-4985 (claims 1 and 2, FIG. 7) includes a tray portion which is accommodated in and discharged from a body of a disk reproducing apparatus, a disk holding portion designed to hold a disk on the tray portion, a disk presence/absence detecting hole made within the range of the disk holding portion of the tray portion, a light emitting means and a light receiving means which are located to be opposite to each other at upper and lower positions with respect to the tray portion at the positions through which the disk presence/absence detecting hole passes on the way where the tray portion is accommodated in and discharged from the reproducing apparatus body, a disk presence/absence determining means for determining the presence/absence of the disk at the disk holding portion using a light received output from the light receiving means while the tray is accommodated, and a stand-by operation directing means for directing a stand-by operation for reproducing the disk when the disk presence/absence determining means determines that the disk is present.
In the disk reproducing apparatus, the disk holding portion is a large-diameter disk holding portion for holding a large-diameter disk. The disk reproducing apparatus further includes a rotary table rotatably arranged on the tray portion, a plurality of small-diameter holding portions formed on the rotary table so as to hold small-diameter disks around the rotary center of the rotary table, a table rotary position detecting hole located at a position which is outside the disk holding portion and the small-diameter disk holding portions of the tray portion and through which the optical axis of the light emitting means and light receiving means passes when the rotary table rotates with the tray portion being accommodated in the body of the reproducing apparatus, and a table rotary position detecting means for detecting the rotary position of the rotary table using the light received output from the light receiving means with the tray being accommodated within the body of the reproducing apparatus.
As described above, this disk reproducing apparatus includes a disk presence/absence determining means for determining the presence/absence of the disk at the disk holding portion using a light received output from the light receiving means while the tray is accommodated. However, since the disk holding portion is a large-diameter disk holding portion which holds a large-diameter disk, the disk presence/absence determining means determines the presence or absence of the large-diameter disk on the large-diameter disk holding portion, and so does not correspond to a disk detecting senor for detecting the presence or absence of the disks (small-diameter disks) placed on the disk placing portions (small-diameter disk holding portions) of the rotary tray (rotary table).
In this disk reproducing apparatus, the table rotary position detecting means for detecting the rotary position of the rotary table using the light received output from the light receiving means with the tray being accommodated within the body of the reproducing apparatus corresponds to the rotary tray sensor for detecting the rotary position (position of the disk placing portion) of the rotary sensor. In this disk reproducing apparatus, the presence/absence of the large-diameter disk placed on the large-diameter disk holding portion is detected by the disk presence/absence determining means, and the rotary position of the rotary table is detected by the table rotary position detecting means.
A disk apparatus disclosed in JP-A-6-150523 (claims 1, 2) includes, in order to detect the stopping position and initial position of each disk placing face of a rotary table and detect the rotary speed of the rotary table, a plurality of slits each having a desired width or concentric skirts having reflecting face sections and a single light emitting/receiving device which cooperates with the skirts. In order to detect the presence/absence of the disk on each disk placing face of the rotary table when the tray comes to a carry-in position, the disk apparatus includes an optical sensor located at a position to receive the light from an optical head. By emitting light from an optical head at a rest position and rotating the rotary table, the light is reflected by the disk if it is present or comes from the optical disk if no disk is present.
In this disk apparatus, the light emitting/receiving device corresponds to the rotary tray sensor for detecting the rotary position of the rotary tray (rotary table), and the optical sensor corresponds to the disk detecting senor for the presence/absence of the disk placed on the disk placing portion (disk placing face) on the rotary tray. Therefore, this disk apparatus detects the presence/absence of the disk to be placed on the disk placing face using the optical sensor and detects the rotary position of the rotary table using the light emitting/receiving device.
A disk identifying device disclosed in JP-A-2000-216415 (claims 1 and 2, FIG. 7) includes a plurality of small holes made on disk placing portions which represent whether or not disks are placed and assigned numbers of the disk placing portions, a light emitting element provided on the lower side of a rotary tray toward the disk placing portions, a first light receiving element provided on the upper side of the rotary tray which produces a detecting signal when it receives the light emitted from the light emitting element which has passed any one of the small holes, and a second light receiving element provided on the lower side of the rotary tray which produces a detected signal when it receives the light emitted from the light emitting element which is reflected from the rear surface of the disk blocking the small hole or the rear surface of the disk placing portion.
This disk identifying device includes a plurality of small holes made on each of disk placing portions, and having different arrangement patterns for the respective disk placing portions, a light emitting element provided on the lower side of a rotary tray toward the disk placing portions, a first light receiving element provided on the upper side of the rotary tray which produces a detecting signal when it receives the light emitted from the light emitting element which has passed any one of the small holes, and a second light receiving element provided on the lower side of the rotary tray which produces a detected signal when it receives the light emitted from the light emitting element which is reflected from the rear surface of the disk blocking the small hole or the rear surface of the disk placing portion.
When the detected signal is transmitted from the first light receiving element, this disk identifying device determines that the disk is not placed on the pertinent disk placing portion, whereas when the detected signal is transmitted from the second light receiving element, the disk identifying device determines that the disk is placed on the pertinent disk placing portion. In this manner, the disk identifying device detects the presence/absence of the disk on the pertinent disk placing portion. Further, the disk identifying device detects the rotary position of the rotary tray by identifying the assigned number of the disk placing portion on the basis of the interval between inputting times of the detected signal and the number of inputs within a prescribed period, etc. Furthermore, the disk identifying device detects the rotary position of the rotary tray by identifying the assigned number of the disk placing portion on the basis of the arrangement pattern of the small holes.
However, although the disk reproducing apparatus disclosed in JP-A-6-4985 is provided with the disk presence/absence determining means for determining the presence/absence of the disk at the disk holding portion using a light received output from the light receiving means while the tray is accommodated, since the disk holding portion is a large-diameter disk holding portion for holding a large-diameter disk, the disk presence/absence determining means determines the presence/absence of the large-diameter disk on the large-diameter disk holding portion. Therefore, the disk presence/absence determining means does not correspond to the disk detecting sensor for detecting the presence/absence of the disk (small-diameter disk) placed on each of the disk placing portions (small-diameter disk holding portions) on the rotary tray (rotary table). Accordingly, the disk reproducing apparatus cannot detect whether or not the disk is present on each of the disk placing portions arranged on the rotary tray.
The disk apparatus disclosed in JP-A-6-150523 detects the presence/absence of the disk to be placed on the disk placing portion (disk mounting face) using the optical sensor and detects the rotary position of the rotary tray (rotary table) using the light emitting/receiving device. However, this disk apparatus requires two sensors of the optical sensor and the light emitting/receiving device for detection of the presence/absence of the disk and of the rotary position of the rotary tray, which is likely to result in a complicated structure and increased costs.
The disk identifying device disclosed in JP-A-2000-216415 employs a single light-emitting element and two light-receiving element for detection of the presence/absence of the disk and of the rotary position of the disk. This is identical to use of two sensors, and is likely to result in a complicated structure and increased costs.